Method for protection of circuits in water-cooled generators

FIELD: electrical engineering.

SUBSTANCE: in water-cooled generator, gas is extracted in N points from generator volume, and measurement of humidity in all points of extraction, according to invention, is carried out with single metre of moisture concentration serially, value of humidity in N extraction point of knowingly driest gas is subtracted from results of current measurements in N-1 point of sample extraction, and speed of differential data variation is used to identify emergency water leaks.

EFFECT: invention provides for detection of emergency mode in water-cooled generators related to water leaks, reduced time required for detection of emergency mode.

2 cl


The invention relates to the technological control of power generators and can be used in power plants to protect from moisture isolation of electrical circuits of the generators.

In the powerful electric generators produces a large quantity of thermal energy (of the order of 250 kW per cubic meter of active volume of the machine), leading to a rise in temperature up to values exceeding the permissible during long-term operation of the elements of the generators (usually not higher than 110°C) [1, str, 319]. To maintain the temperature in the volume of generators used in the cooling system. Modern generators large power systems are used for the cooling of two types [2, section 6]:

- hydrogen-water,

with full water cooling.

In the first case, the cooling water is pumped through the hollow conductors of the stator winding and the rotor and the metal parts are cooled blown through special channels by hydrogen. Such systems are typical for turbo-generators with capacity from 60 to 360 MW.

In systems of the second type of water pumped through the conductors of the stator, the rotor and the special bonds of steel tube active stator are cooled all the elements of the generator. Protection insulation of the windings from moisture is provided by blowing dried air active volume of the generator. Under the basic system characteristic of the turbo-generators with a capacity of 800 MW and more.

A great danger to the health of the generators is moisture insulation of the windings of the stator and rotor, leading to short circuits with catastrophic destruction of the generators [3, 15, 38, 65-68]. The probability of such events could be reduced by passing a cooling gas, which over time increases the concentration of water vapor through the desiccant. Thus, the cooling system includes a source of clean, dry gas to fuel gas generator), gas dehydration, gas cooler, intake fans, piping with shutoff valve [4, p.42-47].

However, the presence of a desiccant gas does not exclude moisture insulation of the windings. This is due to two groups of reasons [4, p.57]. The first group of causes leads to a slow increase in the concentration of water vapor: the failure of the refrigerating machine in the gas drying system, fan failure, or the gas valve. When such failures do not need emergency output the generator operating mode. Enough to increase the recharge oscillator with dry gas or attach a backup drier gas.

The second group of reasons is connected with the water leaks from the ducts of the stator, rotor, inlet hoses, seals or gas cooler. In such cases it is necessary to bring the generator operating mode for the minimum time and to block the flow in the s before as will begin intensive moisturizing elements of the generator (emergency mode).

The known method of relay protection circuit generator voltage generator-transformer with direct water cooling and device for its implementation by the RF patent №2066910 [5]. According to the method on the circuit generator voltage impose alternating currents of two frequencies and determine the equivalent active conductivity of the insulation and cooling medium, and tangent of dielectric loss angle. The data and develop the team off, if at least one of these parameters exceeds the allowable value.

The method has two major drawbacks: low speed and high accuracy. The first drawback stems from the fact that the insulation resistance and the loss tangent is functionally associated with the hydration of isolation, and it is very inertial process. The second drawback associated with the variability of the parameters of the insulation and the cooling water in the normal mode of operation of the generator. According to [2, paragraph 4.12] the insulation resistance should be not less than 10 Megohms per kilovolt voltage winding at a temperature of 30°C and it can be reduced in two times when the temperature is 20°C; similarly for water [4, paragraph 6.12] the specific resistance should be not less than 2000 Ohm·m when the tempo is the atur 25°C and allowed to change up to 500 Ohm·m

The closest technical solution is the system of measurement of the concentration of moisture in the generator with full water cooling TSV - 800 - 2UZ described in section 16 "Ventilation and drying gas turbine generator" operating Instructions TSV - 800 - 2UZ [6, p.51-59]. According to [6] the air in the generator circulates in a closed circuit: dry air is sucked into the fan and under the pressure of 10 to 30 mm of water column is directed to the Central part of the generator. The air flows in both directions from the center to the front parts of the generator of the turbine and exciter), where he is already saturated with moisture, is fed into the drying gas. After the desiccant dry air enters the fan described above.

For controlling the concentration of moisture in the working volume of the generator set 7 knots of air samples: one at the outlet fan (air dry) and three nodes in the frontal parts of the generator. To nodes in the selection connected hygrometers "Wave - 2M". When reaching the testimony humidity 20°C, dew point and above the generator must be disconnected from the mains for 5 minutes [6, paragraph 4.9.23].

Moisture measurement gas more dynamic method than measuring humidity insulation of the windings, since the moisture is distributed in the volume of the generator due to the forced diffusion, defined by the rate of gas flow fans. However, in the description of the technical solution, there are two significant drawbacks.

The first drawback. Low accuracy of measurement of the concentration of moisture. First of all it is connected with the instability of the metrological characteristics of the sensors, convert the concentration of water vapor in the parameter of an electrical signal and, secondly, the dependence of the hygrometer from thermodynamic state of the gas (temperature, pressure)surrounding the sensor. As a rule, near the humidity sensor is placed a resistance thermometer according to the testimony which introduce the necessary amendments in the humidity measurement result. But this is done with the measurement error of the temperature and the pressure is generally not measured.

The second drawback. The diagram and the set of running it operations does not allow to distinguish the nature of the limit values of concentration of vapor in the gas - was it for reasons of the first group (not requiring output of the generator from the working mode) or the second (emergency mode).

The technical problem solved by the invention is the identification emergency mode for generators with water cooling associated with water leaks and reducing the time of its discovery. This object is achieved in that the generator with water cooling in N points produce gas from the volume of the generator, and humidity measurement in all sampling points, according to the invention, the OS is p one measure of the concentration of moisture in series, from the results of the current measurements in the N-1 sampling point is deducted from the value of the humidity in the N-th point selection obviously most of the dry gas and the rate of change of the differential data is judged emergency water leaks.

Consider the implementation of the method on the example outlined above turbine generator TSV - 800 - 2UZ. All 7 points of sampling are connected through a gas switch to one moisture meter. Switches can be gas switch or set of 7 pneumatic relay. However, in this particular case, given the low excess air pressure in the volume of the generator, it is advisable to use the boosters of consumption; they allow to reduce the time of passage of air from the point of sampling to measure moisture. The sequence of inclusion precursors flow and measuring humidity controls microprocessor node that can perform advanced computational procedures or transmit the measurement results to the computer.

The device operates as follows. In the first cycle of measurements (n=1, where n is the cycle number) are derived humidity values 7 sampling points:

where Fi- the humidity value of the first sampling point (i=1, 2,..., N=7), the number in brackets indicates the number of the measurement cycle.

In the second cycle of measurements, done the subject through a known time interval Δt, will the results of the measurements:

Among all sampling points, there is one dedicated, characterized in that the humidity of the gas in the zone selection is minimal. This is the point, which is located behind the fan forcing dry gas. Let us assign to her room n

According to the invention then calculates the difference:

Next, calculate the velocity V1-2changes in the differential data, change the increments humidity values belong to the interval Δt:

Write V1-2(i) means that the rate of increase of the concentration of moisture corresponds to the i-th sampling point; the calculations are performed according to the measurement results in the first and second cycles. In the next cycle of measurement formulas(3), (4), (5) obtains the value of the rate of change of the concentration of moisture V2-3(i) and so on in each cycle to n, after which you will receive the value of the velocity Vn-1-n(i). The values of the rate-of-rise vlagosoderzhaniya gas identify the nature of the process of increasing the concentration of moisture in it (the failure of the gas system or emergency water leakage in the case of the generator).

Consider two numerical examples illustrating the capabilities of the proposed protection method.

Suppose, on the Azania hygrometer in several sampling points were close to the maximum permissible values (15°C dew point), and slew rate concentration is low, for example, of 0.05°C and dew point in a minute. This means, according to (5), dry gas (at the point of selecting the number N) wetland. Conclusion: out of order one of the elements of the system of the drying gas. Although the concentration of moisture in the gas is high, there is no need emergency output of the turbogenerator. It is enough to determine the failed element (dehumidifier, fan and replace it with the backup.

The second case. Concentrations of moisture in the sampling points i, i+1 equal to 4°C and dew point, but the concentration is increasing at a rate of 0.5°C dew point in a minute. This speed increase of the concentration of moisture indicates the presence of a leak of water (for example, in one of the frontal parts of the generator), which is converted into the vapor phase. Although the absolute value of the concentration of moisture is very far from the limit value 15°C dew point, the system must issue the alarm.

The sequence of switching points of the gas in the loop can be any, but preferably each cycle to start with point selection knowingly dry gas. This eliminates the need to store in the memory of the microprocessor, the results of measurements of the concentration of moisture in the other points, because the difference between (3), (4) and speed (5) are calculated immediately upon receipt of the measurement results from other sampling points of gas.

For the adoption of achieving the invention the objectives define the error of the differences of the concentrations of moisture, calculated by expressions (3) and (4). In General, consider the error δ [∆Fk(i)] a difference for the k-th point of the gas in the i-th cycle:

The values included in the expression (6) measurements consist of the true values of the measured variables (Fk0(i) and FN0(i) respectively), the systematic component of the error (θkand θNrespectively) and random components εkand εN. Considering the above-mentioned expression (6) can be written in the form:

δ [∆Fk(i)]=δ[Fk0(i)FN0(i)+θkNkN].

Because, according to the invention, measurement is performed by one measuring channel, the systematic component of error in all measurements is constant, i.e. θkNand their difference is equal to zero. Therefore

and the error difference will be only random component of the error, the feature of which is the standard deviation σ [∆Fk(i)]. To determine pre-calculate the variance of the expression (7):

D [∆Fk(i)]=D[Fk0(i)FN0(i)+εkN]= D[Fk0(i)FN0(i)]+D[εkN].

Variance the difference between Fk0(i) FN0(i)as a constant number equal to zero; it's an expression that is converted to the attribute of thesis the version of the sum (difference) of random variables:

where σk, σN- the average square deviation of the measurement errors of the concentration of moisture collected in the k-th and N-th point, respectively;

ρkNthe correlation coefficient between the random components of the error εkand εN.

The measurement results from all the sampling points obtained by one measurement channel in one cycle of the survey, for a short time (1-2 minutes), therefore, the random error of all measurements is very strongly correlated, i.e. ρkN≈1. Given this condition, the last expression is converted to the form

and standard deviation σ [∆Fk(i)] finally still

Considering the fact that the average RMS errors are single-channel measurements, the difference between them is close to zero. Therefore, the sensitivity and reliability of the data on the rate of change of the concentration of moisture in the gas is provided at small increments of absolute values of vlagosoderzhaniya.

If error, for example, hygrometer "Wave - 2M" equal to 2%, the error difference between two consecutive measurements with an interval of 2 minutes is a hundred times smaller.

This fact, put in the basis of the proposed method of protection circuits of the generator allows stovern to detect small changes in the concentration of moisture in the working volume of the generator rather crude devices. And the definition of slew rate concentration provides sufficient and reliable information for classification reason for the increase in moisture and make an informed decision about entering into force reserve equipment gas system generator or emergency output of the turbogenerator of work.


1. Theoretical fundamentals of heat. Thermal engineering experiment.: The Handbook. / Under the General Ed. Corr.-Corr. USSR Waheguru, Vimsatika. - M.: Energoatomizdat, 1988, book 2.

2. GOST 533-2000 (IEC 34-3-88) interstate standard.

Rotating electrical machines. Turbogenerators. General technical conditions.

3. Alekseev B.A. Definition of States (diagnosis) of large turbogenerators. - M.: Publishing house SC ENES", 2001.

4. RD 153-34.0-45.512-97. Standard instruction manual casamassina system hydrogen cooled generators. Approved by the Department of science and technology of RAO "UES of Russia" 18.06.1997,

5. Description of the invention to the patent of Russian Federation №2066910, CL NN 7/06. The way the relay protection circuit generator voltage generator-transformer with direct water cooling and device for its implementation.

6. Instruction manual turbine generator TW-800-2UZ. Approved by the chief engineer of JSC "Ryazan GRES 18.10.2007,

1. Way protection circuits generators is water cooled, including the measurement of gas moisture in N sampling points of gas from the volume of the generator, characterized in that the measurement of humidity in N sampling points of the gas is realized by one meter in series, from the results of the current measurements in the N-1 sampling point is deducted from the value of the humidity in the N-th point selection obviously most of the dry gas and the rate of change of the differential data is judged emergency water leaks.

2. The method according to claim 1, characterized in that each measurement cycle begins with the sampling point obviously the most dry gas.


Same patents:

Expansion device // 2247461

FIELD: mechanical engineering.

SUBSTANCE: proposed device that can be used in liquid-cooled machines and mechanisms equipped with expansion devices to build up excess pressure is made in the form of tank 1 accommodating piston 2 that mounts detachable weights 4 and sealing rings 3. Piston 2 has barrel 7 whose top part protrudes from tank and is sealed by means of rubber rings 8 disposed in top part of tank; bottom part of piston has holes 12 providing communication between space filled with insulating liquid under piston bottom and annular space between cylindrical surfaces of piston and tank.

EFFECT: enhanced operating reliability of device.

1 cl, 1 dwg

The invention relates to electrical engineering and of electrical engineering and can be used in high-voltage electrical machines, in particular in the turbo-generators with a rated voltage of 110 kV and above

The invention relates to the field of heavy electrical engineering

The invention relates to electrical engineering, in particular to turbine generators with water-cooled windings of the rotor, in which the feed and discharge of water is in addition to the shaft, and the hydraulic pressure in the branches of the windings is created by the difference in centrifugal force between the output and the input of the parallel circuits

FIELD: electricity.

SUBSTANCE: invention refers to electric engineering and can be used in DC-to-AC voltage converters. Bridge inverter - DC-to-AC voltage converter with bridge commutator, with protection of transformer against one-sided saturation includes device for forming voltage of the first half-period with specified value of voltage of the first half-period, calculation device of mean value of voltage of the first half-period and storing the result, device for forming the second half-period of output voltage with mean voltage value equal to stored mean voltage of the first half-period, device for measuring and storing mean voltage of the first half-period, short circuit switch of primary winding of transformer in pauses between formed pulses of the first and the second half-periods, which is formed with switches with two-sided conductivity in adjacent arms of bridge commutator, clock generator of rectangular pulses with period equal to the specified period of output voltage of bridge inverter, circuits transmitting control signals to control inputs of bridge commutator switches. Connection of the above elements is performed as it is specified in application materials.

EFFECT: improvement of mass and dimensions parametres of inverter and decrease of the number of power semiconductor switches owing to excluding an individual switch of short circuit of transformer winding in pauses between formed half-periods.

1 dwg

FIELD: electricity.

SUBSTANCE: invention relates to the field of electrical engineering and is to be implemented to provide for protection of the stator winding of a generator with a collecting bus output against fault to ground. The invention concept is as follows: the device contains zero-sequence current filter, generator, current-to-voltage converter, zero-sequence current filter, orthogonal component shaper, current-to-voltage converter, line voltage sensor, an orthogonal component shaper, incrementor, orthogonal component shaper, zero-sequence voltage sensor, control unit, zero-sequence voltage sensor and comparison circuit. In accordance with the invention concept the orthogonal component shaper is equipped with a reference signal shaper and two multiplier units (the first one and the second one). The data inputs of the first and the second multiplier units are interconnected and connected to the current-to-voltage converter with the three inputs of the reference signal shaper connected to the three outputs of the line voltage sensor.

EFFECT: improvement of the device sensitivity through provision for the device operation immunity to the mains frequency fluctuations and zero-sequence current higher harmonic components.

3 dwg

Electrical machine // 2323512

FIELD: electrical engineering; routine checkup and/or control of synchronous machines in power stations or installations incorporating mentioned electrical machine.

SUBSTANCE: proposed method and device for routine checkup of revolving synchronous electrical machine incorporating wound rotor and wound stator are used to measure stator winding current and voltage, rotor winding current, and temperature at minimum two points in electrical machine using electrical machine simulator and definite currents and voltages. These method and device make is possible to compensate for temporary high reactive power demand without detriment to available active power.

EFFECT: enhanced effectiveness of machine operation and its annual mean power output when using various cooling agents without introducing any modifications in electrical machine.

25 cl, 8 dwg

FIELD: electrical engineering.

SUBSTANCE: proposed method that can be used in off-line power supply systems feeding railway cars equipped with self-excited generators for regulating generator field current includes generator disconnection, selection of pulses arriving from pulse-width modulator with respect to their length, as well as de-energizing of field coil and de-excitation of generator in case pulse length is not kept within desired range. To this end single clocking failures are corrected and generator serviceability is recovered.

EFFECT: reduced transients, enlarged service life of switching devices, enhanced operating reliability, reduced mass, size, and cost, unambiguous trouble location.

1 cl, 1 dwg

FIELD: ground-fault relay protective gear.

SUBSTANCE: proposed device has reference current supply; first and second arc-control reactors; first and second zero-sequence current filters installed at generator first and second leads, respectively; first and second starting elements whose first inputs are connected to secondary windings of first and second arc-control reactors, respectively, and second inputs, to measuring winding of reference current supply; first and second logic units whose first inputs are connected to outputs of first and second starting elements, respectively; first and second selective elements whose outputs are connected to second inputs of first and second logic units, respectively; newly introduced in device are first and second current transformers connected in series with first and second arc-control reactors, respectively, on neutral ends of first and second generators, respectively; these current transformers are connected to reference current supply and input of first low-pass filter, to output of first zero-sequence current filter and to secondary winding of first current transformer and output, to first inputs of first and second selective elements, respectively; first zero-sequence current filter and first current transformer are connected into differential circuit; second low-pass filter has its input connected to output of second zero-sequence current filter and to secondary winding of second current transformer and output, to second inputs of second and first selective elements, respectively; first zero-sequence current filter and second current transformer are connected into differential circuit.

EFFECT: enhanced reliability of selective protection against both steady ground faults and intermittent arcing shorts.

1 cl, 1 dwg

FIELD: relay protection.

SUBSTANCE: the device has a reference current source series-connected to an are extinction reactor, zero phase-sequence current filter installed on the side of generator leadouts, starter whose first input is connected to the secondary winding of the arc extinction reactor, and the second input is connected to the measuring winding of the reference current source, logical unit, whose first input is connected to the starter output, selective component, whose output is connected to the second input of the logical unit, current transformer series-connected to the arc extinction reactor on the side of the generator neutral, low-frequency filter, whose input is connected to the output of the zero phase-frequency current filter and to the secondary winding of the current transformer, and the output is connected to the selector input, the zero phase-frequency current filter and the current transformer are connected according to the differential circuit.

EFFECT: provided selectivity of protection both at stable ground faults and at alternate arc faults.

1 dwg

FIELD: constant- and variable-frequency ac supply systems.

SUBSTANCE: proposed ac generator protective device has measuring component, final element, two threshold elements, ac voltage regulator, and frequency measuring element; measuring component is made in the form of auxiliary winding placed in same slots as stator inducing winding, number of pole pairs of auxiliary winding being greater by odd number of times than that of inducing winding; input of frequency measuring element is connected to measuring component through ac voltage regulator; input of first threshold element is connected to measuring component; input of second threshold element is connected to output of frequency measuring element; outputs of both threshold elements are connected to final element coil.

EFFECT: enlarged functional capabilities of protective device.

1 cl, 3 dwg

FIELD: electrical engineering; power stations.

SUBSTANCE: proposed generator control process includes control of temperature readings, their comparison with setting values, and if they do not exceed these setting values, generator is allowed to keep running, otherwise instruction is sent to disconnect generator from load. If temperature reading exceeds setting value, temperature rise above the latter is computed and converted into control signal and reactive power is reduced as function of this signal; as soon as reactive power is brought to specified minimum, control signal is stored and stored value is subtracted from current value of control signal. If this difference is positive, turbine power regulator setting is reduced as function of this value and if control signal drops below value affording minimal reactive power, memory is changed over to monitoring mode.

EFFECT: enhanced reliability.

1 cl, 1 dwg

FIELD: electrical engineering; voltage regulation for dc generators, primarily those of off-line power supply systems.

SUBSTANCE: proposed dc generator voltage regulator has fuse, voltage measuring element, transistor switch, self-excitation relay, two diodes, overvoltage protective unit, and two resistors. Overvoltage protective unit is provided with output break contact and its measuring input is connected to third lead of voltage regulator which is connected to plus bus through series-connected transistor switch shorted out by break contact of self-excitation relay and through output break contact of overvoltage protective unit; power bus of overvoltage protective unit is connected to cathode of second diode and its common bus, to minus bus.

EFFECT: enhanced reliability of voltage regulator and protective gear.

2 cl, 4 dwg

Electric generator // 2262788

FIELD: power engineering; power stations.

SUBSTANCE: proposed synchronous generator is connected to power transmission line through communication unit, protection unit, and circuit breaker. Exciter connected to generator rotor has its input connected to field regulator. Input of the latter is connected to generator stator through current and potential transformers. Upon occurrence of short circuit in line, regulator functions to force current through generator rotor. Protection unit operates and sends instruction for opening line circuit breaker. At the same time signal is passed through shaper to regulator for reducing field current. By moment when circuit breaker contacts open generator rotor current reduces. That is why generator rotor magnetic field changes to a lower extent when circuit breaker opens. Lower overvoltage is induced in rotor thereby reducing insulation breakdown probability in rotor and exciter.

EFFECT: enhanced reliability.

2 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: in method for determining electromagnetic time constant of squirrel-cage rotor of asynchronous motor with rotor (ADKR), in order to determine current value of electromagnetic time constant of rotor, to the computing device there entered are design parametres of ADKR in the form of active resistance of stator winding and inductivity of magnetisation circuit, leakage coefficients of magnetic flows of stator and rotor in terms of stator current. During the process, there entered is information on the value of phase current and voltage and on phase displacement angle between voltage and current of stator winding. By means of computing device there determined is electromagnetic time constant of rotor by mathematical formula which is specified in application materials and which includes all the required parameters available for direct measurement in any ADKR mode.

EFFECT: providing economical and steady operation of variable-frequency electric drive on the basis of asynchronous motor with squirrel-cage rotor.

1 dwg

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and can be used for testing electrical and mechanical damages of induction motors supplied from frequency converters. Multi-phase voltage with 50%-symmetric pulse-width modulation is fed intermittently during operations or breaks. Note here that appearance of current in phase is controlled. Availability of current flowing in motor phase at the moment above and current character will testify either availability or presence of motor winding damage.

EFFECT: possibility to test frequency-controlled motor by rated voltage in both operation and breaks.

FIELD: physics.

SUBSTANCE: different sides of the outer surface of the body of the monitored object (electric machine) are fitted with at least four partial discharge measurement sensors, connected to recording apparatus. The sensors are moved in turns within the borders of the surface of the side of the body on which they are fitted until a maximum signal is received at the output of the sensor. The sensor is fixed on that position on the surface of the body. The output signal waveform of the sensor is recorded using the recording apparatus. After fixing the first sensor, the next sensors are fixed if their output signal waveforms coincide with that of the first sensor. The lag time of signals received by sensors from the first received signal is measured. Location of a defect is determined from the value of lag time, and the type of the discharge phenomenon is determined from the output signal waveform.

EFFECT: simple and reliable determination of location of a defect.

6 dwg

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and the technology of operating turbo-generators, is meant for controlling thermal and technical state of turbo-generators, as well as cooling systems of turbo-generators, and can be used for diagnosing powerful turbo-generators with hybrid cooling. According to the proposed method, at the output of each stator slot temperature of the winding bar inside it is measured, as well as temperature of active steel of the stator, temperature of cold distillate at the input of the stator winding, temperature of cold gas at the output of the gas cooler, current and voltage of the stator and rotor. The square of the present value of stator current is determined, as well as the square of gross power of the turbo-generator, square of rotor current, power loss in the rotor winding and temperature of the rotor in corresponding load conditions. Present and reference temperature rise of the winding inside the stator slot are determined, as well as present and reference temperature rise of active steel, and present and reference temperature rise of the rotor winding for each present load condition. The ratio of the present temperature rise of the winding inside the stator slot to the reference temperature rise of the winding inside the stator slot is determined, as well as the ratio of the present temperature rise of active steel to the reference temperature rise of active steel, and the present temperature rise of the rotor to the reference temperature rise of the rotor, from the results of which presence of thermal defect is determined.

EFFECT: increased accuracy and effectiveness of controlling and diagnosing turbo-generators.

2 dwg, 3 tbl

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering. The proposed method comprises measuring pulsed electromagnetic field of breakage current for every commutation section with the help of magnetically-sensitive elements arranged between the area the sections are jointed to commutator in and the start of contact surfaces on, both leaving and leading commutator segments. Breakage current quantisation and arc existence algorithm is preset proceeding from invariability of charge value for every quantisation time interval. Note here that, beforehand, standard dependence of the weight of material discharged due to electric-arc erosion in every pair of contact surfaces upon the product of maximum breakage current amplitude, for the given quantisation interval, by normalised charge specified in constructing quantisation algorithm, is formed. Actual weight of aforesaid discharged material is determined by comparing it with standard dependence. Data obtained is summed for the worst commutation cycle to be determined from the maximum total weight.

EFFECT: higher validity, fast data deriving.

5 dwg

FIELD: electricity.

SUBSTANCE: present invention relates to electrical engineering, particularly to stations for testing electric supporting machines of a rolling stock. The station for testing electric machines has a control unit with measuring devices, a production base with elements for fastening at least, two electric machines, mainly dc current machines, a kinematic link for joining armatures of test electric machines, power supply unit, load resistor unit, switching unit, connected through control circuits and power cables. At the base there are fastening elements in form of threadolets, placed in accordance with connection sizes of standard series of electric supporting machines. The control unit with measuring devices is also connected to a computer and has measuring devices with sensors of temperature of windings and angular speed of drive shafts of the machines. The kinematic link of the machines is in form of a V-belt drive with a belt pulling device. The power supply unit has a device for blocking supply, which is linked to temperature and angular speed sensors. The power supply unit is independent and consists of a generator of different values and types of supply current and voltage and several detachable columns with the corresponding contact part of the test machines. The load resistor unit has a current and voltage stabiliser and an electric output with provision for connecting a working load.

EFFECT: more versatile device with the objective of carrying out safer and comprehensive tests of the whole standard series of electric supporting machines.

3 dwg